Tamping roller



Sept. 23,1952 J. M. PARAMYTHIOTI TAMPING ROLLER Filed Sept. 8, 1948 3Sheets-Sheet 1 n v 3% Z kl a Patented Sept. 23; 195 2 S rArENr 'rA P-INGRo rEn g Jean Mi hel r a ythi fi, assay F an e; as

signer to Socit Anonyme dos Anciens Etablissements AJbaret,Rantigny'QFrance, a conica in p Fr nc g s t se t mber 8,1948, Serial No.48,273 In Erance September-424; 19.47 I

vided. Such small single-wheel .tamping. rollers "ar 'irequen iid e irona engi ewe 1 h m t eo a d a m nt ned i operative position andsteered'bymeansof a beam meander? When starting" operations with such ajriachine theenginetorque meetswith quite a high drag-or rollingresistance due to the sinkingof theirollerinto the ground, and as aresultexertsa considerable reaction on the irame of the machine, andthis reaction has to be taken up by the driver'of the roller;

e Qlain s. (01.180

In th ex m la emb m n hown mine l and 2 the single wheel rollercomprises as show ,arecesseddrum'structure I welded to side It is oneobjectof the"presentinvention to devise a roller of thBQlIIBEXIB type-inwhich the 7 above defined reaction of the engine torque 'against'the-f-rame and thecoupling beam is substantially reduced or completelysuppressed; f

Another object is in a rollerof any type to counter-balance throughmechani m" m an b e t P 91 fi i gresistance ofthe-rolle ,vvit th'isend.in v-iew,- I propose to replace the axial direct transmissionbetween-theengine'an'd a the roller by anepicyclic transmission,' which allows forthe-introduction of an 'auxiliarytorque adapted for automaticallycompensating i the variable-value of the"rolling-resistance torque. This"compensating torque' -is -produced by a counterweight which is moved bythe epicycli'c transmission to rotate about its axis-to an angularposition' inwhich it exerts on'said epicyclic transmission ,a torque.approximately equal and oppositeto" the rolling resistance torque.

According to armain feature of my invention, the epicyclic'drivetransmission is an epicyclic gearinghaving its sun-gears and itsplanetarycarrier connected respectively to one of the three memberscomprisin the drive member, the counterweight and the roller.

The invention will now be described with ref- =erenceito 'theattached'drawings where similar iteferencea'arerusedtodesignatesimilar orequivalentfelements.

Figure 1 is a diagrammatic side view in section of a single-Wheel rollerprovided with a counterweight drive means according to the invention.

Figures 2, 3 and 4 are views of the three embodiments of the inventionin cross-section on line 11-11 of Figure 1.

in the giirection of travelfoffthe-"roller.

: fle s? ea formed wit inward p sse 16 vcentrally mounting the roller-ona fixedarglshaft je carridon racket supports 5 secured t the-sideesills6 of a suitable frame. Said frame p violed with legs 1 for resting it onthe e e awemm na n nher I m e 1 e ne 15 releas s irritat t he en lin 9connecteat r u ree e m dli 9 he "mu WW??? of' th'e. s sand the adjacentflange 2 Ion theffixed axle-shaft A through the-medium oi a g'rrierriber i3' extending through ithe' "boss ihubinehiber I3 andthevhub member carries at its inner enda gear Hi. keyed'tdlit. of .theopposite flange carries 'a gear l fi'k eyed -vto j'it. Said gearsmeshiwith a; pairiofv gearsflfi' and i l respectively keyedon a.crossshaft i8 i otatahly extending through a counterw vsum;sneer fromthe; axlej tthrough a pair of a, as {23 attneu perends of whichffbossesformed that v are ireelyinounted on; the iaxleeshait. 'lT h'e ax e-Shafthas Secured to. it an arcuate s r ng; platemember 21' serving as alimiting stopifor the counterweight at the end of lth. strol e of thelatter. v I 11 s .c e rth t b v sc i d semi-When forms an epicyclicgearing] in which gears Y L4 and 1.5 are sun-gear elements inmesh withpntarygearst'lfi' and. ll respectivelyof 5pm alrycerrie elem n formed bythe. 001111, "rwei eh i9j'which is rqtatablgabout a, common" aids. withea s a 1.

rrwrl zreaeiiy. be understood that u q eng vtieiu te" tar d 's' c en ineQwiliflth ugh th sptrpcket ha n ll. drive in rotation heea we gh ,At irt. the. resistance or "the roller to 'forward "motion is high and will,'throughlthe gears I541, oppose rotation of the shaft, 181. Adcordingly'the ciounterweightv will fifst swing up.- war l am nd the Will -Shaft;as shcwii'i'n flai counterweight thus produces a condition of uribalancewhich, for a certain elevation of the counterweight will reach a valueequal to the resistance to forward movement. The counterweight will thenstop and the roller will start to be driven through the action of theshaft 3' 3 which will revolve within the counterweight. Immediately uponstarting, the resistance to forward movement will fall to a lower valueand the counterweight return backwards to a lower position, andsubsequently adapt its position to the variable value of the opposingtorque. Whenever the resistance to forward motion becomes excessive, thecounterweight will tend to move 7 further up, but its upward stroke islimited by abutment against the spring member 2|.

In the exemplary embodiment above described the planetary carrier isformed by the counterweight which is rotatable about the same axis asthat of the roller.

The epicyclic drive is subjected to three separate torques, namely theenginetorque, the torque exerted by the counterweight which variesaccording to the swinging angular position from its lower rest positionto an active position, and the opposing torque which is the greatest atstarting. The mass of the counterweight and its lever-arm areconstructionally so 'correlated that in the fully elevated position ofthe counterweight the torque exerted by it will balance the startingtorque, so that the counterweight will always correspond to the normalopposing torque applied to the roller when riding on the ground. Let C1,C2, C3 be the algebraic values of the drive torque, the counterweighttorque and the opposing torque respectively, then the equation ofequilibrium for the epicyclic transmission in that position will beC1+C2+Ca=0. Now, in the epicyclic gearing, the said couples are. appliedto three separate elements, namely the two sun-gears and theplanetary-carrier. Let A1, A2, A3 be the respective algebraic values ofthe torques corresponding to one of the sungears, the planetary-carrierand the other sungear, then the equation of balance can also be writtenas A1+Az+A3:0. Both the equations being homogeneous it is obvious thatthe operation of the mechanism will be independent of the correspondencebetween the terms in A and those in C. Otherwise stated, if A2designates the torque applied to the planetary-carrier, that torque maycorrespond either to the drive torque or to the counterweights torque oryet to the opposing torque, while the torques exerted on the twosun-gears will respectively correspond to the remaining two torques.

' Further forms of embodiment of the invention will now be describedwherein the'planetarycarrier is rigid either with the roller oralternasupports 5 rigid with the side-sills B of the frame. The wheel [2which constitutes the drive memher in this embodiment is freelyrotatable on the axle shaft and is rigid with a gear l4 meshing with apinion 16 secured on a planetary shaft l8 freely rotatable in one of theflanges 2. The latter therefore plays the part of the planetarycarrierand the other planetary gear I! is in 'mesh with the gear l5 which asshown is rigid with the counterweight freely rotatable on the shaft 4.

On starting, the planetary-carrier 2 is subjected to the startingtorque, and the planetary shaft 18 is on the other hand subjected to azero torque, so that rotation of the drive pinion l2 4 will causerotation of the planetary shaft and the counterweight will thereuponrise until the starting torque is approximately balanced by the torquedue to the counterweight when motion will take place. a

v In the modification shown in Fig. 4, the shaft 4 is mounted forrotation in the bearings 5 and is rigid on the one hand with a sprocketwheel l2 and on the other hand with the planetary-carrier 50, both keyedto the said shaft. The counterweight l9 is rigid with the gear l5 and isfreely rotatable on said shaft, while the pinions 11 and I6 of theplanetary shaft ll! of the planetary-carrier 50 respectively mesh withthe gear 15 and the gear-teeth 14 solid with the roller.

Upon starting, rotation of the gear I 2 and consequently of the shaft 4rotates the planetarycarrier 50, and, since the resistance exerted onthe pinion I6 is greater than that on the pinion H, the pinion IE willroll on the gear-teeth ll of the roller and rotation of theplanetary-carrier will cause the counterweight to swing up. When thecounter-weight is brought to rest at its position of balance in whichits torque balances the starting torque, it will on the other hand, bethe pinion I! that will roll along the teeth l5 which now arestationary, while the pinion I6 of the planetary-shaft in rotating willrotate the roller.

While in all of the embodiments shown the counterweight is arrangedwithin the roller, the invention contemplates the possibility ofproviding a counterweight rotatably mounted outside the roller proper.Moreover the driving connection according to the invention may beexecuted in various manners without departing from the invention asclaimed in the following claims.

What I claim is:

1. A tamping roller comprising in combination, a frame, a transverseshaft mounted in said frame, a roller mounted on said shaft andsupporting said frame, a driving wheel mounted on .said shaft, anepicyclic gearing having two sungear members and a planetary carriermember coaxial with said shaft, and a weight having its center ofgravity eccentric to said shaft rigidly connected with one of saidmembers, the other two members being respectively rigid with said rollerand with said driving wheel.

2. A tamping roller according to claim 1 in which the planetary carrieris rigid with the counterweight.

3. A tamping roller according to claim 1 in which the planetary carrieris rigid with the re ler.

4. A tamping roller according to claim 1, in

which the planetary carrier is rigid with the driving wheel.

JEAN MICHEL PARAMYTHIO'I'I.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES Zubaty Oct. 20, 1925

